Warhammer 40k is a tactical tabletop game. It was created by gamesworkshop in 1987. Players build armies using a point system based on the many, and extremely colorful factions in the Warhammer 40k. Then players field their armies on the battlefield, where they can win by doing objectives, or outright slaughtering the opposing army. This makes for a very fluid and fun tabletop war games, and was very much a big influence to a lot of popular war games of the past. If you ever played HeroClix, Mageknight, Mechwarrior Dark Age, it's a very similar experience. Additionally, there is a huge and expanding collection of factions and sub factions, all dripping with story rich detail. As a player, you can very much find a army of beliefs or values that you treasure, making finding a favorite army a pretty fun process. There are tons of narratives, game modes and configurations, campaigns and evolving army mechanics for a ton of replayability. It's definitely a game that should be experienced once!